Electrically-heated tank or reservoir.



F. G. CLARK, P. ACKERMAN & C. E. CANSFIELD.

ELECTRICALLY HEATED TANK 0R RESERVOIR.

APPLICATION FILED JAN. 18, l9l8.

Patented Nov. 12, 1918 lnventars:

tent to the required temperature,

operation of the heaters being for heating the 'ronon'ro, om'nmo, CANADA, LIMITED, or roaonro, CANADA, A coaronnrron or ONTARIO,

Original application filed. July 5, 1917, Serial No. 178,622. Divided and ASSIGNORS TO THE TORONTO POWER COMPANY on RESERVOIR.

Patented Nov. 12, 1918.

this application file January 18,

1918. Seria1No.21 2,523. v

To all whom it may concern Be it known that we, FARLEY GRANGER CLARK, a citizen of the United States of America, PAUL ACKERMAN, .a citizen of Switzerland, and CHARLES ERNEST CANS- FIELD, a subject of the King of Great Britain, all .residin at the cit of Toronto, in

Brovince of Oncertain new and useful Improvements in Electrically-Heated Tanks or Reservoirs,

(this being a division of application Serial No. 178,622, filed July 5, 1917;) and we hereby declare that the following is a full, clear, and exact description of the same.

This invention relates to a tank or reservoir heated by two or more electric heater elements, either or both of which may be selectively used for raising the tank conto vsupply the normal daily demands and the increased and the urgent demands occurring periodically and at irregular intervals; the-capacity of the tank and the heat-generating power of the heater elements being correctl proportioned for this purpose, and the se ective controlled either manually or automatical y. p

In carrying'out the invention, one of the heater elements, which maybe termed the main heater,

tank content, or arranged to be temporarily cut out, by means of a time switch, during predetermined periods of peak loads, the capacity of the tank and the heat-generating power of this heater element being so proportioned as to satisfy the normal daily demands, such use obtaining the usual preferential rates for electric service. The other of the heater elements, which may be termed the auxiliary heater, is brought into use when the tank content is required to meet urgent or increased demands, the main heater element being placed so that the whole of the tank content may be uniformly heated to the required temperature, and the auxiliary heater element being placed so that the upper part of the tank content may be quickly raised to the required temperature, either when in the tank, or as it flows to the discharge pi e.

The drawing represents a sectiona elevational view of a preferred form of our invention.

the bottom of the tank. outlet p 1pe from the tank, and 5 represents a switch 17 to the terminal 6 may be continuously used Details of the electric heater elements and the control devices are not shown, as we may use any type of electric heater element or elements and any type of manual static control.

1 represents a tank or reservoir which is prefera ly covered with heat insulation 2. 3 represents the inlet pipe entering the tank or reservo r and discharging preferably near 4 represents the drain pipe and cock. A represents the main electric heater element, and B the auxiliary heater element. a, a and b, 6 respectivel represent the terminals of the respective eater elements A and B.

Y 10 and 11 represent the two line wires connecting to some source of electric power, and 12 and 13 are the connections between the line wires 10 and 11 and the terminals a and a respectively, of the main heater A. 14 and 15 are corresponding connections to the auxiliary heater B, 14 connecting directly to the heater terminal Z2, and 15 connectingthrough the manually-controlled switch 16 or the thermostatically-controlled The control switch 16 and the thermostatic switch 17 are shown shunting each other, so that the circuit of the electric heater B may be closed independently by either of the two switches.

The heater elements A and B are of the band type, and are placed on the outside surface of the tank, the main heater A encircling the tank near the bottom, and the auxiliary heater B encircling the tank near the top, the main heater being employed 'to raise the whole of the tank content to the required temperature to supply the normal daily demands, and the auxiliary heater being employed to meet increased and urgent demandsoccurring periodically and at irregular intervals, the heat generating power of the heater elements being correctly proportioned to the capacity of the tank for this purpose, and the selective operation of the heaters being controlled either manually or automatically.

The preferential type of heater elements for the heaters A and B, is that shown and described in our concurrent application, Serial No. 178,621, filed July 5th, 1917.

.The auxiliary heater can be controlled or thermo-' either manually by means of the switch 16,

closed at times of excessive demand, or controlled automatically by means of 'a thermostatic switch which will close the circuit through the auxiliary heater B at a predetermined low temperature and open it when a predetermined high temperature has been attained.

The drawing indicates the principle of utilizing the main heater A to uniformly heat the whole of the tank content to a temperature which will provide a storage supply ready for constant use, to meet the normal daily demand; of utilizing the auxiliary heater B to assist the main heater A in supplying any increased demand,- by quickly raising the temperature of part of the ta content; and of utilizing either a thermostatic or manual device for bringing the auxiliary heater into use, the thermostatic device automatically maintaining the temperature in the top of the tank at a predetermined degree.

The heaters may be used in connection with a tank or reservoir designed for any particular purpose, and the heaters may consist of single or multiple elements.

By arranging and operating the heaters in this way, the tank content may be efficiently and economically heated to supply all reasonable normal and increased demands, the heaters and the tank capacity being proportioned to the demand.

Having thus fully described the nature of our invention, What we claim as new and desire to secure by Letters Patent, is

1. An electrically-heated tank comprising a main electric heater encircling the tan near the bottom, an auxiliary electric heater encircling the tank near the top, and means controlling the circuit of the current through said heaters.

Y 2. An electrically-heated tank comprising a main electric heater encircling the tan near the bottom, an auxiliary electric heater encircling the tank near the top, electrical conductors for the main and auxiliary heaters, and means selectively controlling the circuit of the current to the heaters, for energizing the main heater to heat the entire tank content, and the auxiliary heater to heat the upper portion of the tank content.

Toronto, January ninth, 1918.

FARLEY GRANGER CLARK. PAUL ACKERMAN. CHARLES ERNEST CANSFIELD. 

